A lubrication device for the drive screw pair of a screw press.

Abstract

This utility model belongs to the field of lubrication technology for screw presses, specifically disclosing a lubrication device for the transmission screw pair of a screw press, including: a main oil inlet pipe, a distributor, a branch oil inlet pipe, a slide return oil pipe, and a gland return oil pipe; one end of the main oil inlet pipe is connected to an oil pump station, and the other end is connected to the oil inlet on the distributor; the distributor is detachably mounted on one side of the slide and is also provided with multiple oil outlets; one end of the branch oil inlet pipe is connected to the oil outlet of the distributor, and the other end is connected to a first oil inlet passage provided on the slide; the main nut is provided with a second oil inlet passage connected to the first oil inlet passage; one end of the slide return oil pipe is connected to the first oil return passage provided on the side wall of the slide cavity; one end of the gland return oil pipe is connected to the second oil return passage provided on the gland; the dual oil return path design achieves efficient, continuous, and cyclical lubrication of the friction pair between the main screw and the main nut, significantly improving the reliability of equipment operation.

Description

Technical Field

[0001] This utility model belongs to the field of lubrication technology for screw presses, and more specifically, relates to a lubrication device for the transmission screw pair of a screw press. Background Technology

[0002] Screw presses, as important forging and pressing equipment, are widely used in machinery manufacturing, metallurgy, automotive, aerospace and other fields, mainly for plastic forming processes such as die forging, upsetting, and extrusion of metal materials. Their core working principle is to convert the rotational motion of the main screw into the vertical reciprocating linear motion of the slide block through a screw pair mechanism, thereby achieving impact or static pressure forming of the workpiece. During this transmission process, the screw pair formed by the main screw and the main nut bears enormous alternating loads and impact forces, and there is significant relative sliding between the contact thread surfaces, resulting in severe sliding friction. This friction not only leads to energy loss but also directly causes severe wear of the main nut, while generating a large amount of heat. If heat dissipation is not timely, the local temperature of the screw pair can easily rise sharply, leading to "seizure" failure, seriously affecting the operational stability, processing accuracy and service life of the equipment. Therefore, effective and reliable lubrication and cooling of the screw pair is a key technical aspect to ensure the long-term, efficient and safe operation of the screw press. The lubrication condition of the screw pair directly affects the reliability, maintenance cost and production efficiency of the equipment, and has become a long-standing technical challenge in this field.

[0003] To address the wear and overheating seizing problems caused by sliding friction in screw presses, the commonly used solution in existing technologies is to form a lubricating film between the thread surfaces using a lubricating medium. This reduces the friction coefficient between the main screw and the main nut, decreases frictional wear, and allows the flow of the lubricating medium to carry away some of the heat generated by friction, thus alleviating the overheating seizing phenomenon. Regarding the specific lubrication method, considering that the screw pair operates intermittently during operation, the clearance between the thread surfaces is small, and the operating environment may contain dust, debris, and other impurities, existing technologies primarily use grease as the lubricating medium. When using grease for lubrication, the lubricating medium is typically supplied in two ways: one is periodic manual lubrication, where operators inject grease into the thread surfaces of the screw pair using a grease gun or similar tool through pre-set grease holes or nozzles on the equipment according to the equipment maintenance cycle, ensuring the thread surfaces are covered with a layer of grease; the other is semi-automatic lubrication, which uses a simple grease storage tank and a metering valve on the equipment to automatically deliver a set amount of grease to the mating surfaces of the screw pair at set time intervals, reducing the frequency of manual operation. The existing technology selects grease as the lubricating medium mainly because grease has good adhesion, can maintain adhesion between the thread teeth for a long time, and is not easily lost due to the movement of the screw pair. At the same time, its sealing performance is relatively good, which can prevent external impurities from entering the screw pair to a certain extent and avoid impurities from aggravating the wear of the thread teeth.

[0004] Despite the various methods employed in existing technologies, grease-based lubrication still suffers from inherent drawbacks, making it difficult to fundamentally solve the problems of wear and overheating seizing in helical pairs. For example, grease has extremely poor fluidity and is a semi-solid substance. It is difficult to achieve uniform and sufficient penetration and distribution in the complex thread gaps of helical pairs under high loads and high speeds. Especially when the main screw rotates at high speeds or is subjected to impact loads, the grease cannot be replenished to the areas of most intense friction in time, leading to easy rupture of the local oil film, resulting in boundary lubrication or even dry friction, which exacerbates the wear of the main nut. Secondly, due to its poor fluidity, grease has very limited heat dissipation capacity and cannot effectively remove the large amount of heat generated by friction through circulation like liquid lubricating oil. In addition, existing grease lubrication methods are mostly "consumable" lubrication, meaning that the grease is constantly squeezed, oxidized, and contaminated during use, eventually becoming ineffective and requiring regular large-scale replenishment or replacement, resulting in a huge waste of lubricating materials. At the same time, waste grease is difficult to recycle effectively, which not only increases the operating costs of enterprises but also pollutes the environment, which is inconsistent with the development concept of modern green manufacturing. Utility Model Content

[0005] To address the aforementioned deficiencies or improvement needs of existing technologies, this utility model provides a lubrication device for the transmission screw pair of a screw press. Through a dual oil return path design, it achieves efficient, continuous, and cyclical lubrication of the friction pair between the main screw and the main nut, effectively solving the problems of uneven lubrication, poor heat dissipation, and seizing associated with traditional grease. This significantly improves the reliability and service life of the equipment. Simultaneously, it ensures efficient recovery of the lubricating oil after lubrication, avoiding waste and environmental pollution. Furthermore, the recovered lubricating oil can be recycled after cooling and filtration, greatly reducing lubricating oil consumption and conforming to the concept of green manufacturing.

[0006] To achieve the above objectives, this utility model provides a lubrication device for a screw pair in a screw press transmission. The screw press includes a slider, a main nut disposed in a cavity in the middle of the slider, and a pressure cap disposed at the upper end of the slider to limit the movement of the main nut. The lubrication device comprises: a main oil inlet pipe, a distributor, a branch oil inlet pipe, a slider return oil pipe, and a pressure cap return oil pipe; wherein:

[0007] One end of the main oil inlet pipe is connected to the oil pump station, and the other end is connected to the oil inlet on the distributor;

[0008] The distributor is detachably mounted on one side of the slider and is also provided with multiple oil outlets.

[0009] One end of the oil inlet branch pipe is connected to the oil outlet of the distributor, and the other end is connected to the first oil inlet passage provided on the slider.

[0010] The main nut is provided with a second oil inlet passage that is connected to the first oil inlet passage.

[0011] One end of the slider return oil pipe is connected to the first return oil passage provided on the side wall of the slider cavity, and is used to collect the lubricating oil overflowing from the lower end of the main nut;

[0012] One end of the gland return oil pipe is connected to the second return oil passage provided on the gland, which is used to collect the lubricating oil overflowing from the upper end of the main nut.

[0013] Furthermore, the lubrication device further includes a first return oil main pipe and a second return oil main pipe; wherein:

[0014] The inlet end of the first oil return main pipe is connected to both the slider oil return pipe and the gland oil return pipe via a T-connector, and its outlet end is connected to the second oil return main pipe.

[0015] The second return oil main is located on one side of the machine body, and its outlet end is connected to the oil pump station.

[0016] Furthermore, both the oil inlet main pipe and the first oil return main pipe are flexible hoses.

[0017] Furthermore, multiple second oil inlet outlets are respectively located at the root and surface of the internal thread in the middle region of the main nut.

[0018] Furthermore, one first oil inlet passage corresponds to at least two second oil inlet passages;

[0019] A fan-shaped chamber is formed between the outer surface of the main nut and the cavity sidewall of the slider, and the first oil inlet passage is connected to multiple second oil inlet passages through the fan-shaped chamber.

[0020] Furthermore, the first return oil path is horizontal and its inlet is close to the bottom surface of the inner cavity of the slider.

[0021] Furthermore, the second return oil path is horizontal and close to the bottom surface of the gland.

[0022] Furthermore, the pressure cap is provided with a vent hole, which is vertically arranged, with one end located on the upper surface of the pressure cap and the other end connected to the second return oil circuit.

[0023] Furthermore, there is at least one oil inlet branch pipe, and each oil inlet branch pipe corresponds one-to-one with the first oil inlet path on the slider.

[0024] Furthermore, the oil inlet branch pipe is a copper pipe, while the slider return oil pipe and the gland return oil pipe are both steel pipes;

[0025] The oil inlet branch pipe, the slider return oil pipe, and the gland return oil pipe are respectively laid along the contour of the slider surface through connectors.

[0026] In summary, compared with the prior art, the above-described technical solution conceived by this utility model can achieve the following beneficial effects:

[0027] 1. The lubrication device of this utility model achieves efficient, continuous, and cyclical lubrication of the friction pair between the main screw and the main nut through a dual oil return path design. It effectively solves the problems of uneven lubrication, poor heat dissipation, and easy seizing of traditional grease, significantly improving the reliability and service life of the equipment. At the same time, it ensures that the lubricating oil can be efficiently recovered after completing the lubrication task, avoiding waste and environmental pollution. Furthermore, the recovered lubricating oil can be recycled after cooling and filtration, greatly reducing the consumption of lubricating oil and conforming to the concept of green manufacturing.

[0028] 2. The lubrication device of this utility model ensures sufficient lubrication in the high-load area by directly delivering lubricating oil to the deepest and closest contact areas of the main screw and the main nut meshing. At the same time, this position is located inside the starting section of the thread meshing, which effectively avoids the direct compression of the lubricating oil when the main screw is screwed in, thus preventing the oil from overflowing prematurely. This ensures that the lubricating oil stays between the friction pairs for a sufficient time, improving the continuity of lubrication and the cooling effect, and preventing local dry friction and thermal damage.

[0029] 3. The lubrication device of this utility model significantly improves the symmetry and coverage of lubrication by ensuring that lubricating oil enters the multiple circumferential thread meshing areas of the main screw and the main nut evenly, effectively reducing local wear and thermal stress concentration, and improving transmission smoothness and reliability.

[0030] 4. The lubrication device of this utility model forms a complete oil return passage by setting a first oil return main pipe and a second oil return main pipe, which effectively ensures the efficient return and recycling of lubricating oil and improves the system integration and operational reliability. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the lubrication device according to an embodiment of the present invention;

[0032] Figure 2 This is a cross-sectional view of the lubrication device according to an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of the structure at point A in embodiment A of this utility model;

[0034] Figure 4 This is a schematic diagram of the structure at point B in embodiment B of this utility model.

[0035] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically:

[0036] 1-Main body, 2-Main nut, 201-Second oil inlet circuit, 3-Slider, 301-First oil inlet circuit, 302-First oil return circuit, 4-Pressure cap, 401-Second oil return circuit, 402-Vent hole, 5-Main oil inlet pipe, 6-Distributor, 7-Branch oil inlet pipe, 8-Slider return pipe, 9-Pressure cap return pipe, 10-First oil return pipe, 11-Second oil return pipe. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the present utility model and are not intended to limit the present utility model. Furthermore, the technical features involved in the various embodiments of the present utility model described below can be combined with each other as long as they do not conflict with each other.

[0038] Please refer to Figures 1 to 4This utility model provides a lubrication device for a screw pair in a screw press, comprising: a main oil inlet pipe 5, a distributor 6, a branch oil inlet pipe 7, a slide return oil pipe 8, and a gland return oil pipe 9; one end of the main oil inlet pipe 5 is connected to an oil pump station, and the other end is connected to the oil inlet on the distributor 6; the distributor 6 is detachably mounted on one side of the slide 3, and is also provided with multiple oil outlets; one end of the branch oil inlet pipe 7 is connected to the oil outlet of the distributor 6, and the other end is connected to a first oil inlet passage 301 provided on the slide 3; the main nut 2 is provided with a second oil inlet passage 201 communicating with the first oil inlet passage 301; one end of the slide return oil pipe 8 is connected to a first oil return passage 302 provided on the side wall of the cavity of the slide 3, for collecting lubricating oil overflowing from the lower end of the main nut 2; one end of the gland return oil pipe 9 is connected to a second oil return passage 401 provided on the gland 4, for collecting lubricating oil overflowing from the upper end of the main nut 2.

[0039] Understandably, the lubrication device of this utility model achieves efficient, continuous, and cyclical lubrication of the friction pair between the main screw and the main nut 2 through the design of a dual oil return path. This effectively solves the problems of uneven lubrication, poor heat dissipation, and easy seizing of traditional grease, significantly improving the reliability and service life of the equipment. At the same time, it ensures that the lubricating oil can be efficiently recovered after completing the lubrication task, avoiding waste and environmental pollution. Furthermore, the recovered lubricating oil can be recycled after cooling and filtration, greatly reducing the consumption of lubricating oil and conforming to the concept of green manufacturing.

[0040] It should be noted that the screw press is a common pressure device in the prior art, including a slider 3, a main nut 2 disposed in the cavity in the middle of the slider 3, and a pressure cap 4 disposed on the upper end of the slider 3 to limit the main nut 2.

[0041] It should be noted that, in this embodiment, the lubricating oil is a low-viscosity lubricating oil, which utilizes its excellent fluidity to quickly penetrate into the threaded gap between the main screw and the main nut 2, forming a uniform lubricating film and significantly reducing the sliding friction resistance and wear between the friction pairs. Simultaneously, it facilitates heat conduction, working in conjunction with the oil inlet branch pipe 7, the slider return oil pipe 8, and the gland return oil pipe 9 to achieve efficient circulating heat dissipation, effectively preventing the screw pair from seizing due to overheating, and improving transmission efficiency and equipment operational stability.

[0042] In an optional embodiment, multiple outlets of the second oil inlet 201 are respectively located at the root and surface of the internal thread in the middle region of the main nut 2, so as to directly deliver lubricating oil to the deepest contact area and the closest contact area of ​​the main screw and the main nut 2, ensuring sufficient lubrication in the high-load area; at the same time, this position is located inside the starting section of the thread engagement, which effectively avoids the direct compression of the lubricating oil when the main screw is screwed in, which would cause the oil to overflow prematurely, ensuring that the lubricating oil stays between the friction pairs for a sufficient time, improving the continuity of lubrication and the cooling effect, and preventing local dry friction and thermal damage.

[0043] In an optional embodiment, one first oil inlet passage 301 corresponds to at least two second oil inlet passages 201; a fan-shaped chamber is formed between the outer surface of the main nut 2 and the cavity sidewall of the slider 3, and the first oil inlet passage 301 communicates with multiple second oil inlet passages 201 through the fan-shaped chamber to ensure that the lubricating oil enters the multiple circumferential thread meshing areas of the main screw and the main nut 2 evenly, significantly improving the symmetry and coverage of lubrication, effectively reducing local wear and thermal stress concentration, and improving transmission smoothness and reliability.

[0044] In an optional embodiment, the first return oil passage 302 is horizontal and its inlet is close to the bottom surface of the inner cavity of the slider 3, which is used to effectively collect the lubricating oil and frictional heat debris deposited at the bottom of the inner cavity of the slider 3 due to gravity, ensuring that the high-temperature lubricating oil overflowing from below the main nut 2 is recovered in a timely and sufficient manner, and avoiding oil stagnation that leads to poor heat dissipation or impurity accumulation.

[0045] In an optional embodiment, the second oil return path 401 is horizontal and close to the bottom surface of the gland 4, so as to efficiently collect the lubricating oil overflowing from the upper end of the main nut 2 and the heat it carries, to prevent the oil from accumulating in the gap between the gland 4 and the main screw, and to ensure smooth oil return.

[0046] In an optional embodiment, the pressure cap 4 is provided with a vent 402. The vent 402 is vertically arranged, with one end located on the upper surface of the pressure cap 4 and the other end connected to the second oil return passage 401 to form a venting channel. This can effectively balance the internal oil return area of ​​the pressure cap 4 with the external atmospheric pressure, prevent the lubricating oil from flowing out smoothly due to negative pressure, thereby improving the oil return efficiency, avoiding oil stagnation or leakage, and ensuring the continuous and reliable operation of the lubrication system.

[0047] In an optional embodiment, there is at least one oil inlet branch pipe 7, and the oil inlet branch pipe 7 corresponds one-to-one with the first oil inlet passage 301 on the slider 3. This is used to achieve independent oil supply at multiple points, ensuring that the lubricating oil is accurately and evenly delivered to the second oil inlet passage 201 at different circumferential positions of the main nut 2. This effectively covers the entire circumferential friction area of ​​the helical pair, improves the uniformity and reliability of lubrication, avoids wear and overheating caused by insufficient local lubrication, and ensures the stable operation of the transmission helical pair.

[0048] In an optional embodiment, the oil inlet branch pipe 7 is a copper pipe, and the slider return oil pipe 8 and the gland return oil pipe 9 are both steel pipes. The oil inlet branch pipe 7, the slider return oil pipe 8 and the gland return oil pipe 9 are respectively laid along the surface contour of the slider 3 through connectors to ensure that the pipes are laid in a curved manner and are not easily broken. At the same time, it can save space, avoid interference with moving parts, enhance the regularity and safety of the pipeline, and effectively improve the reliability and maintenance convenience of the lubrication system.

[0049] Furthermore, the lubrication device also includes a first oil return main pipe 10 and a second oil return main pipe 11; the inlet end of the first oil return main pipe 10 is connected to both the slider oil return pipe 8 and the gland oil return pipe 9 via a tee connector, and its outlet end is connected to the second oil return main pipe 11; the second oil return main pipe 11 is located on one side of the machine body, and its outlet end is connected to the oil pump station to form a complete oil return passage, effectively ensuring the efficient return and recycling of lubricating oil, and improving system integration and operational reliability.

[0050] In an optional embodiment, both the oil inlet main pipe 5 and the first oil return main pipe 10 are flexible hoses, which are used to effectively adapt to the mechanical vibration and displacement generated by the reciprocating motion of the slider 3 during the operation of the screw press, and avoid pipeline stress concentration or fatigue fracture caused by rigid connection.

[0051] In an optional embodiment, the second return oil main pipe 11 is a steel pipe, and is laid along the surface of the machine body 3 through a connector, in order to save space, avoid interference with moving parts, enhance the regularity and safety of the pipeline, and effectively improve the reliability and maintenance convenience of the lubrication system.

[0052] The working principle of this utility model is as follows: During operation, the oil pump station delivers low-viscosity lubricating oil through the main oil inlet pipe 5 to the first oil inlet 601 of the distributor 6. After passing through the distributor 6, the lubricating oil enters the first oil inlet passage 301 inside the slider 3 through multiple oil inlet branch pipes 7. The lubricating oil then flows into the fan-shaped cavity formed by the outer surface of the main nut 2 and the side wall of the slider 3 cavity, and is then diverted to at least two outlets of the second oil inlet passage 201 located in the middle region of the main nut 2 at the thread root and thread surface, precisely injecting it into the deepest contact area where the main screw and the main nut 2 mesh, thus achieving... Forced lubrication and cooling in high-load areas; during the rotation of the main screw, the lubricating oil fully covers the thread friction surface, reducing the friction coefficient and carrying away frictional heat; the lubricating oil overflows from the top and bottom of the main nut 2, respectively. The lubricating oil overflowing from the bottom is collected by the first return oil passage 302 near the bottom of the inner cavity of the slider 3, while the oil overflowing from the top is collected through the second return oil passage 401 at the bottom of the gland 4. The two return oil passages converge into the first return oil main pipe 10 via a three-way connector, then flow into the second return oil main pipe 11 arranged along the machine body, and finally return to the oil pump station.

[0053] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0054] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0055] In this invention, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model, and not to limit it; those skilled in the art will readily understand that the above description is only a preferred embodiment of this utility model, and is not intended to limit this utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A lubrication device for a screw pair in a screw press, the screw press comprising a slide block (3), a main nut (2) disposed in the central cavity of the slide block (3), and a pressure cap (4) disposed at the upper end of the slide block (3) to limit the main nut (2), characterized in that, The lubrication device includes: a main oil inlet pipe (5), a distributor (6), a branch oil inlet pipe (7), a slide return oil pipe (8), and a gland return oil pipe (9); wherein: One end of the oil inlet pipe (5) is connected to the oil pump station, and the other end is connected to the oil inlet on the distributor (6); The distributor (6) is detachably mounted on one side of the slider (3), and is also provided with multiple oil outlets; One end of the oil inlet branch pipe (7) is connected to the oil outlet of the distributor (6), and the other end is connected to the first oil inlet passage (301) provided on the slider (3); The main nut (2) is provided with a second oil inlet passage (201) that is connected to the first oil inlet passage (301); One end of the slider return oil pipe (8) is connected to the first return oil passage (302) provided on the side wall of the slider (3) cavity, and is used to collect the lubricating oil overflowing from the lower end of the main nut (2); One end of the pressure cap return oil pipe (9) is connected to the second return oil passage (401) provided on the pressure cap (4) to collect the lubricating oil overflowing from the upper end of the main nut (2).

2. The lubrication device according to claim 1, characterized in that, The lubrication device further includes a first return oil main pipe (10) and a second return oil main pipe (11); wherein: The inlet end of the first oil return main pipe (10) is connected to both the slider oil return pipe (8) and the gland oil return pipe (9) through a three-way connector, and its outlet end is connected to the second oil return main pipe (11). The second return oil main pipe (11) is located on one side of the machine body, and its outlet end is connected to the oil pump station.

3. The lubrication device according to claim 2, characterized in that, Both the oil inlet pipe (5) and the first oil return pipe (10) are hoses.

4. The lubrication device according to any one of claims 1-3, characterized in that, Multiple outlets of the second oil inlet (201) are respectively located at the root and surface of the internal thread in the middle region of the main nut (2).

5. The lubrication device according to any one of claims 1-3, characterized in that, One of the first oil inlet passages (301) corresponds to at least two of the second oil inlet passages (201); A fan-shaped chamber is formed between the outer surface of the main nut (2) and the cavity sidewall of the slider (3), and the first oil inlet passage (301) is connected to multiple second oil inlet passages (201) through the fan-shaped chamber.

6. The lubrication device according to any one of claims 1-3, characterized in that, The first return oil path (302) is horizontal and its inlet is close to the bottom surface of the inner cavity of the slider (3).

7. The lubrication device according to any one of claims 1-3, characterized in that, The second return oil passage (401) is horizontal and close to the bottom surface of the cap (4).

8. The lubrication device according to any one of claims 1-3, characterized in that, The pressure cap (4) is provided with a vent hole (402). The vent hole (402) is vertically arranged, with one end located on the upper surface of the pressure cap (4) and the other end connected to the second return oil passage (401).

9. The lubrication device according to any one of claims 1-3, characterized in that, There is at least one oil inlet branch pipe (7), and the oil inlet branch pipe (7) corresponds one-to-one with the first oil inlet path (301) on the slider (3).

10. The lubrication device according to any one of claims 1-3, characterized in that, The oil inlet branch pipe (7) is a copper pipe, while the slider return oil pipe (8) and the gland return oil pipe (9) are both steel pipes. The oil inlet branch pipe (7), the slider return oil pipe (8), and the cap return oil pipe (9) are respectively laid along the surface contour of the slider (3) through connectors.

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